Analysis of conveyor belts in winter Mediterranean cyclones

The relevance of the midlatitude conveyor belt model to Mediterranean cyclones (MCs) is examined using data from two winters. Eight MCs, which exhibit typical midlatitude cyclone structure, were scrutinized and their conveyor belts were examined. The analysis was based on satellite imagery, isentropic wind maps, vertical cross-sections of potential and equivalent potential temperatures, and air back-trajectories. The conveyor belts found in the studied MCs were similar to the common features of midlatitude cyclones, except for three aspects. First, the warm conveyor belt was not associated with massive organized cloudiness in five of the eight cyclones since it consisted of dry air originated from the Saharan desert. Second, the anticyclonic branch of the cold conveyor belt was not found in half of the MCs. Third, the dry air intrusion originated north of the cyclone and extended southward around it, unlike its common midlatitudinal northwest–southeast orientation. This is consistent with the relatively small baroclinic vertical-westward tilt of the cyclones analyzed.